i bought this car about 2months ago it had the stock lt1.it spun a bearing and bent the #8 rod. i had a proffesionl rebuild done and now is considered a 383 stroker. i'm not mechanically inclined. my question is that itappears to be running rich, should i purchase a aftermarket performance chip? will that automatically take care of my fueland other computer related issues? or have the stock memcal chip recalibrated.thanks ..

 

If your engine is now a 383 and no changes were done to the PCM or fuel injection, the engine should be running lean instead of rich. I suggest you take a look at the O2 sensors, fuel pressure & pressure regulator, and the temp sensors. Recalibrating the MEMCAL is not the way to go till you fix theexistingproblem.

 

my mistake, it is running lean. can you tell me what the fuel pressure should be..thank you.

 

still somewhat confused. it was suggested that i take a look at the o2 sensors,fuel pressure,pressure regulator, and temp sensors. there are no codes being thrown at this time. can i assume all are ok? and if so what direction would you go to have the recalabration completed..can a local gm dealer do this or if someoneknows ofanybody who can do this, i would appreciate your imput..thanks..p.s. the ingine is running lean.

 

Sensors have a habit of drifting with time, and the PCM has no way of telling if they are sending the proper data or not.The PCM will complain only if they are totally broken, or way out of whack. You can use a scanner to read the sensor data & see if it makes sense. Unless you have an adjustable pressure regulator the fuel pressure cannot be changed, but you can verify if it is within spec using a FI pressure gage. Changing fuel pressure without tuning the PCM is a waste of time is the PCM will counter your change by changing the injector pulse length. You need to have the PCM tuned for your mods, either with the help of a dyno (best case), or get a mail order tune from a place like PCM for Less.

 

thanks for all your help pete..